Copper redeposition and surface enrichment during the dissolution of Al-Cu alloys in different concentrations of NaCl solution. Part 1 - electrochemical measurements

摘要

Purpose - The paper aims to study the dissolution of Al, Al-3.84%Cu, Al-5.22%Cu and Al-11%Cu alloys in different concentrations of NaCl (10-5-10-1 M). Design/methodology/approach - The approach is to use open circuit potential (OCP) and potentiostatic polarization measurements. Findings - Results obtained showed that, as the Cu content was increased in the Al-Cu alloys, a steady state potential was rapidly reached. Addition of different concentrations of CuCl{sub}2 to 0.5M NaCl demonstrated that by increasing the concentration of CuCl{sub}2 up to 2 ppm a greater increase in the OCP towards more anodic value occurred from the moment of immersion. Further increases in the concentration of CuCl{sub}2, up to 600 ppm, exhibited the same behavior. Originality/value - The results of the study reveal that cathodic current was controlled by the oxygen in solution, while the anodic current increased with increased Cu content in the alloy.